The invention relates to a circuit arrangement for transferring a d.c. voltage, the circuit arrangement comprising a switchable smoothing network arranged between an input and an output terminal and operative with respect to a reference potential, the smoothing network comprising at least a series resistor and connected thereto a parallel branch formed by a first capacitor, which may be arranged in series with a first resistor, and a second capacitor, which may be arranged in series with a second resistor, and which is connectable to the output terminal for increasing the time constant of the smoothing network.
In known circuits of this type which can be used, for example, to control a voltage-controlled oscillator, a varying voltage is usually transferred. When the second capacitor is disconnected there is, as a rule, a voltage across it which differs from the voltage across the first capacitor. As soon as the second capacitor is switched into the circuit, a charging or discharging current flows to it, and in correspondence therewith, a voltage jump is produced which acts on the transferred voltage and may have detrimental results. For example, the oscillator may be brought outside its pull-in range, which produces a new change-over. The oscillator pulls-in again, etc. It takes quite a long period of time before the control circuits have definitely changed over to the slow time constant.